1. Field of the Invention
The present invention relates to placer mining devices, and more particularly to a hinged sluice box structure that is collapsible for easy transport to be thereafter erected on site into its operative deployment by interlocks that render this deployment convenient while also minimizing leakage losses of the contained water flow in the course of its use.
2. Description of the Prior Art
The mining of gold or other precious metals aggregated in alluvial deposits, known generally as placer mining, has been practiced by man since the dawn of time, most often by water irrigated methods suggested by the alluvial aggregation itself. While quite effective in using water flow for segregating the heavier precious metal components from the rest of the particulates, these mining processes are heavily dependent on an abundant local water supply which is often affected by local weather patterns, seasonal snow melts and the like that, by way of long term trends, some times cumulatively change a well irrigated landscape into an arid one.
Of course, the random reversals of periodic weather patterns, even those determined by long term trends, are associated with water flows in old, dry stream beds that can serve the mining of old alluvial deposits which were left untouched for some time. This solitude of an arid landscape interrupted by a recent deluge, therefore, is more likely to be productive although usually not well serviced by a network of roads, along with its absence of convenient water flows, reduces the incidence of earlier inspections by others, resulting in a commensurately increased potential of discovery, and a compact, easily transported mining mechanism that recirculates a limited quantity of water is therefore best suited for the search efforts of these more remote sites.
In the recent past the logistic concerns associated with this same solitude have dominated the development focus, resulting in various robust vehicle or trailer borne high volume mining assemblies like those exemplified in U.S. Pat. No. 6,065,606 issued to Bonner; U.S. Pat. No. 6,843,376 issued to Dube et al.; U.S. Pat. No. 7,093,719 issued to Roper, U.S. Pat. No. 7,461,746 issued to Egge et al.; and many others. While suitable for the purposes intended, these robust structures seek to maximize recovery from a site that is already found. Of course, once the prospect of a productive site is known the complement cost and burden of its transport to the remote location become a matter of business accounting, an analytical process that is wholly distinct from the concerns of a remote desert search.
To assist in the successful prospecting of these remote desert areas an effective, highly portable mechanism is required which is easily carried over rough terrain from one alluvial accumulation to another and various examples of such structures have been suggested in the prior asrt exemplified by the teachings of U.S. Pat. No. 3,799,415 to Tidd; U.S. Pat. No. 4,375,491 to Honig; U.S. Pat. No. 4,592,833 to Perdue; U.S. Pat. No. 4,676,891 to Braa et al.; Des. U.S. Pat. No. 302,018 to Messenger et al.; U.S. Pat. No. 5,785,182 to Ashcraft; U.S. Pat. No. 5,927,508 to Plath; and many others. Once again, while each of these prior examples are suitable for their intended purpose, the interests of portability have often dominated the function obtained and functions like process water conservation and its recovery are rarely addressed.
To resolve these concerns I, and thereafter others, have sold to the public folding sluice box assemblies characterized by nested hinged segments which would then be unfolded and secured by fasteners employing wing nuts to fix the unfolded assembly into a common trough within which the alluvial matter is screened and inspected. Examples of these structures were earlier sold by my business Royal Manufacturing Industries, Inc., 600 W. Warner Ave., Santa Ana, Calif. 92707, under model designation ‘Stream Sluice’ and are currently also sold by JOBE Wholesale, 13911 Pioneer Rd, Apple Valley, Calif. 92307 under model number 6506. Although quite effective as a collapsible sluice structure, these prior sluice arrangements are inherently prone to leakage at each of the hinged, and fastened, folds resulting in unwanted losses of the water stream, and with it also the losses of the heavier matter that may have been collected at the hinge.
Moreover, the inherently imprecise nature of a threaded fastener enabled process has invariably resulted in large overlapping gaps at each hinged joint and the resulting water leakages precluding any realistic conservation of these early water flows and its recirculation. To resolve the foregoing defects I now describe a collapsible sluice structure provided with an inventively improved hinge interlock which effects a tighter panel proximity when deployed to allow for continuous water recovery and recirculation.